diff options
Diffstat (limited to 'Documentation/mic/mic_overview.txt')
-rw-r--r-- | Documentation/mic/mic_overview.txt | 54 |
1 files changed, 30 insertions, 24 deletions
diff --git a/Documentation/mic/mic_overview.txt b/Documentation/mic/mic_overview.txt index 73f44fc3e715..074adbdf83a4 100644 --- a/Documentation/mic/mic_overview.txt +++ b/Documentation/mic/mic_overview.txt @@ -12,10 +12,19 @@ for the X100 devices. Since it is a PCIe card, it does not have the ability to host hardware devices for networking, storage and console. We provide these devices -on X100 coprocessors thus enabling a self-bootable equivalent environment -for applications. A key benefit of our solution is that it leverages -the standard virtio framework for network, disk and console devices, -though in our case the virtio framework is used across a PCIe bus. +on X100 coprocessors thus enabling a self-bootable equivalent +environment for applications. A key benefit of our solution is that it +leverages the standard virtio framework for network, disk and console +devices, though in our case the virtio framework is used across a PCIe +bus. A Virtio Over PCIe (VOP) driver allows creating user space +backends or devices on the host which are used to probe virtio drivers +for these devices on the MIC card. The existing VRINGH infrastructure +in the kernel is used to access virtio rings from the host. The card +VOP driver allows card virtio drivers to communicate with their user +space backends on the host via a device page. Ring 3 apps on the host +can add, remove and configure virtio devices. A thin MIC specific +virtio_config_ops is implemented which is borrowed heavily from +previous similar implementations in lguest and s390. MIC PCIe card has a dma controller with 8 channels. These channels are shared between the host s/w and the card s/w. 0 to 3 are used by host @@ -38,7 +47,6 @@ single threaded performance for the host compared to MIC, the ability of the host to initiate DMA's to/from the card using the MIC DMA engine and the fact that the virtio block storage backend can only be on the host. - | +----------+ | +----------+ | Card OS | | | Host OS | +----------+ | +----------+ @@ -47,27 +55,25 @@ the fact that the virtio block storage backend can only be on the host. | Virtio| |Virtio | |Virtio| | |Virtio | |Virtio | |Virtio | | Net | |Console | |Block | | |Net | |Console | |Block | | Driver| |Driver | |Driver| | |backend | |backend | |backend | - +-------+ +--------+ +------+ | +---------+ +--------+ +--------+ + +---+---+ +---+----+ +--+---+ | +---------+ +----+---+ +--------+ | | | | | | | | | | |User | | | - | | | |------|------------|---------|------- - +-------------------+ |Kernel +--------------------------+ - | | | Virtio over PCIe IOCTLs | - | | +--------------------------+ -+-----------+ | | | +-----------+ -| MIC DMA | | +------+ | +------+ +------+ | | MIC DMA | -| Driver | | | SCIF | | | SCIF | | COSM | | | Driver | -+-----------+ | +------+ | +------+ +--+---+ | +-----------+ - | | | | | | | | -+---------------+ | +------+ | +--+---+ +--+---+ | +----------------+ -|MIC virtual Bus| | |SCIF | | |SCIF | | COSM | | |MIC virtual Bus | -+---------------+ | |HW Bus| | |HW Bus| | Bus | | +----------------+ - | | +------+ | +--+---+ +------+ | | - | | | | | | | | - | +-----------+---+ | | | +---------------+ | - | |Intel MIC | | | | |Intel MIC | | - +---|Card Driver | | | | |Host Driver | | - +------------+--------+ | +----+---------------+-----+ + | | | |------|------------|--+------|------- + +---------+---------+ |Kernel | + | | | + +---------+ +---+----+ +------+ | +------+ +------+ +--+---+ +-------+ + |MIC DMA | | VOP | | SCIF | | | SCIF | | COSM | | VOP | |MIC DMA| + +---+-----+ +---+----+ +--+---+ | +--+---+ +--+---+ +------+ +----+--+ + | | | | | | | + +---+-----+ +---+----+ +--+---+ | +--+---+ +--+---+ +------+ +----+--+ + |MIC | | VOP | |SCIF | | |SCIF | | COSM | | VOP | | MIC | + |HW Bus | | HW Bus| |HW Bus| | |HW Bus| | Bus | |HW Bus| |HW Bus | + +---------+ +--------+ +--+---+ | +--+---+ +------+ +------+ +-------+ + | | | | | | | + | +-----------+--+ | | | +---------------+ | + | |Intel MIC | | | | |Intel MIC | | + | |Card Driver | | | | |Host Driver | | + +---+--------------+------+ | +----+---------------+-----+ | | | +-------------------------------------------------------------+ | | |